| //===----- CGCall.h - Encapsulate calling convention details ----*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // These classes wrap the information about a call or function |
| // definition used to handle ABI compliancy. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "CGCall.h" |
| #include "CodeGenFunction.h" |
| #include "CodeGenModule.h" |
| #include "clang/Basic/TargetInfo.h" |
| #include "clang/AST/Decl.h" |
| #include "clang/AST/DeclCXX.h" |
| #include "clang/AST/DeclObjC.h" |
| #include "clang/Frontend/CompileOptions.h" |
| #include "llvm/Attributes.h" |
| #include "llvm/Support/CallSite.h" |
| #include "llvm/Target/TargetData.h" |
| |
| #include "ABIInfo.h" |
| |
| using namespace clang; |
| using namespace CodeGen; |
| |
| /***/ |
| |
| // FIXME: Use iterator and sidestep silly type array creation. |
| |
| const |
| CGFunctionInfo &CodeGenTypes::getFunctionInfo(const FunctionNoProtoType *FTNP) { |
| return getFunctionInfo(FTNP->getResultType(), |
| llvm::SmallVector<QualType, 16>()); |
| } |
| |
| const |
| CGFunctionInfo &CodeGenTypes::getFunctionInfo(const FunctionProtoType *FTP) { |
| llvm::SmallVector<QualType, 16> ArgTys; |
| // FIXME: Kill copy. |
| for (unsigned i = 0, e = FTP->getNumArgs(); i != e; ++i) |
| ArgTys.push_back(FTP->getArgType(i)); |
| return getFunctionInfo(FTP->getResultType(), ArgTys); |
| } |
| |
| const CGFunctionInfo &CodeGenTypes::getFunctionInfo(const CXXMethodDecl *MD) { |
| llvm::SmallVector<QualType, 16> ArgTys; |
| // Add the 'this' pointer unless this is a static method. |
| if (MD->isInstance()) |
| ArgTys.push_back(MD->getThisType(Context)); |
| |
| const FunctionProtoType *FTP = MD->getType()->getAsFunctionProtoType(); |
| for (unsigned i = 0, e = FTP->getNumArgs(); i != e; ++i) |
| ArgTys.push_back(FTP->getArgType(i)); |
| return getFunctionInfo(FTP->getResultType(), ArgTys); |
| } |
| |
| const CGFunctionInfo &CodeGenTypes::getFunctionInfo(const FunctionDecl *FD) { |
| if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) |
| if (MD->isInstance()) |
| return getFunctionInfo(MD); |
| |
| const FunctionType *FTy = FD->getType()->getAsFunctionType(); |
| if (const FunctionProtoType *FTP = dyn_cast<FunctionProtoType>(FTy)) |
| return getFunctionInfo(FTP); |
| return getFunctionInfo(cast<FunctionNoProtoType>(FTy)); |
| } |
| |
| const CGFunctionInfo &CodeGenTypes::getFunctionInfo(const ObjCMethodDecl *MD) { |
| llvm::SmallVector<QualType, 16> ArgTys; |
| ArgTys.push_back(MD->getSelfDecl()->getType()); |
| ArgTys.push_back(Context.getObjCSelType()); |
| // FIXME: Kill copy? |
| for (ObjCMethodDecl::param_iterator i = MD->param_begin(), |
| e = MD->param_end(); i != e; ++i) |
| ArgTys.push_back((*i)->getType()); |
| return getFunctionInfo(MD->getResultType(), ArgTys); |
| } |
| |
| const CGFunctionInfo &CodeGenTypes::getFunctionInfo(QualType ResTy, |
| const CallArgList &Args) { |
| // FIXME: Kill copy. |
| llvm::SmallVector<QualType, 16> ArgTys; |
| for (CallArgList::const_iterator i = Args.begin(), e = Args.end(); |
| i != e; ++i) |
| ArgTys.push_back(i->second); |
| return getFunctionInfo(ResTy, ArgTys); |
| } |
| |
| const CGFunctionInfo &CodeGenTypes::getFunctionInfo(QualType ResTy, |
| const FunctionArgList &Args) { |
| // FIXME: Kill copy. |
| llvm::SmallVector<QualType, 16> ArgTys; |
| for (FunctionArgList::const_iterator i = Args.begin(), e = Args.end(); |
| i != e; ++i) |
| ArgTys.push_back(i->second); |
| return getFunctionInfo(ResTy, ArgTys); |
| } |
| |
| const CGFunctionInfo &CodeGenTypes::getFunctionInfo(QualType ResTy, |
| const llvm::SmallVector<QualType, 16> &ArgTys) { |
| // Lookup or create unique function info. |
| llvm::FoldingSetNodeID ID; |
| CGFunctionInfo::Profile(ID, ResTy, ArgTys.begin(), ArgTys.end()); |
| |
| void *InsertPos = 0; |
| CGFunctionInfo *FI = FunctionInfos.FindNodeOrInsertPos(ID, InsertPos); |
| if (FI) |
| return *FI; |
| |
| // Construct the function info. |
| FI = new CGFunctionInfo(ResTy, ArgTys); |
| FunctionInfos.InsertNode(FI, InsertPos); |
| |
| // Compute ABI information. |
| getABIInfo().computeInfo(*FI, getContext(), TheModule.getContext()); |
| |
| return *FI; |
| } |
| |
| CGFunctionInfo::CGFunctionInfo(QualType ResTy, |
| const llvm::SmallVector<QualType, 16> &ArgTys) { |
| NumArgs = ArgTys.size(); |
| Args = new ArgInfo[1 + NumArgs]; |
| Args[0].type = ResTy; |
| for (unsigned i = 0; i < NumArgs; ++i) |
| Args[1 + i].type = ArgTys[i]; |
| } |
| |
| /***/ |
| |
| void CodeGenTypes::GetExpandedTypes(QualType Ty, |
| std::vector<const llvm::Type*> &ArgTys) { |
| const RecordType *RT = Ty->getAsStructureType(); |
| assert(RT && "Can only expand structure types."); |
| const RecordDecl *RD = RT->getDecl(); |
| assert(!RD->hasFlexibleArrayMember() && |
| "Cannot expand structure with flexible array."); |
| |
| for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end(); |
| i != e; ++i) { |
| const FieldDecl *FD = *i; |
| assert(!FD->isBitField() && |
| "Cannot expand structure with bit-field members."); |
| |
| QualType FT = FD->getType(); |
| if (CodeGenFunction::hasAggregateLLVMType(FT)) { |
| GetExpandedTypes(FT, ArgTys); |
| } else { |
| ArgTys.push_back(ConvertType(FT)); |
| } |
| } |
| } |
| |
| llvm::Function::arg_iterator |
| CodeGenFunction::ExpandTypeFromArgs(QualType Ty, LValue LV, |
| llvm::Function::arg_iterator AI) { |
| const RecordType *RT = Ty->getAsStructureType(); |
| assert(RT && "Can only expand structure types."); |
| |
| RecordDecl *RD = RT->getDecl(); |
| assert(LV.isSimple() && |
| "Unexpected non-simple lvalue during struct expansion."); |
| llvm::Value *Addr = LV.getAddress(); |
| for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end(); |
| i != e; ++i) { |
| FieldDecl *FD = *i; |
| QualType FT = FD->getType(); |
| |
| // FIXME: What are the right qualifiers here? |
| LValue LV = EmitLValueForField(Addr, FD, false, 0); |
| if (CodeGenFunction::hasAggregateLLVMType(FT)) { |
| AI = ExpandTypeFromArgs(FT, LV, AI); |
| } else { |
| EmitStoreThroughLValue(RValue::get(AI), LV, FT); |
| ++AI; |
| } |
| } |
| |
| return AI; |
| } |
| |
| void |
| CodeGenFunction::ExpandTypeToArgs(QualType Ty, RValue RV, |
| llvm::SmallVector<llvm::Value*, 16> &Args) { |
| const RecordType *RT = Ty->getAsStructureType(); |
| assert(RT && "Can only expand structure types."); |
| |
| RecordDecl *RD = RT->getDecl(); |
| assert(RV.isAggregate() && "Unexpected rvalue during struct expansion"); |
| llvm::Value *Addr = RV.getAggregateAddr(); |
| for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end(); |
| i != e; ++i) { |
| FieldDecl *FD = *i; |
| QualType FT = FD->getType(); |
| |
| // FIXME: What are the right qualifiers here? |
| LValue LV = EmitLValueForField(Addr, FD, false, 0); |
| if (CodeGenFunction::hasAggregateLLVMType(FT)) { |
| ExpandTypeToArgs(FT, RValue::getAggregate(LV.getAddress()), Args); |
| } else { |
| RValue RV = EmitLoadOfLValue(LV, FT); |
| assert(RV.isScalar() && |
| "Unexpected non-scalar rvalue during struct expansion."); |
| Args.push_back(RV.getScalarVal()); |
| } |
| } |
| } |
| |
| /// CreateCoercedLoad - Create a load from \arg SrcPtr interpreted as |
| /// a pointer to an object of type \arg Ty. |
| /// |
| /// This safely handles the case when the src type is smaller than the |
| /// destination type; in this situation the values of bits which not |
| /// present in the src are undefined. |
| static llvm::Value *CreateCoercedLoad(llvm::Value *SrcPtr, |
| const llvm::Type *Ty, |
| CodeGenFunction &CGF) { |
| const llvm::Type *SrcTy = |
| cast<llvm::PointerType>(SrcPtr->getType())->getElementType(); |
| uint64_t SrcSize = CGF.CGM.getTargetData().getTypeAllocSize(SrcTy); |
| uint64_t DstSize = CGF.CGM.getTargetData().getTypeAllocSize(Ty); |
| |
| // If load is legal, just bitcast the src pointer. |
| if (SrcSize >= DstSize) { |
| // Generally SrcSize is never greater than DstSize, since this means we are |
| // losing bits. However, this can happen in cases where the structure has |
| // additional padding, for example due to a user specified alignment. |
| // |
| // FIXME: Assert that we aren't truncating non-padding bits when have access |
| // to that information. |
| llvm::Value *Casted = |
| CGF.Builder.CreateBitCast(SrcPtr, llvm::PointerType::getUnqual(Ty)); |
| llvm::LoadInst *Load = CGF.Builder.CreateLoad(Casted); |
| // FIXME: Use better alignment / avoid requiring aligned load. |
| Load->setAlignment(1); |
| return Load; |
| } else { |
| // Otherwise do coercion through memory. This is stupid, but |
| // simple. |
| llvm::Value *Tmp = CGF.CreateTempAlloca(Ty); |
| llvm::Value *Casted = |
| CGF.Builder.CreateBitCast(Tmp, llvm::PointerType::getUnqual(SrcTy)); |
| llvm::StoreInst *Store = |
| CGF.Builder.CreateStore(CGF.Builder.CreateLoad(SrcPtr), Casted); |
| // FIXME: Use better alignment / avoid requiring aligned store. |
| Store->setAlignment(1); |
| return CGF.Builder.CreateLoad(Tmp); |
| } |
| } |
| |
| /// CreateCoercedStore - Create a store to \arg DstPtr from \arg Src, |
| /// where the source and destination may have different types. |
| /// |
| /// This safely handles the case when the src type is larger than the |
| /// destination type; the upper bits of the src will be lost. |
| static void CreateCoercedStore(llvm::Value *Src, |
| llvm::Value *DstPtr, |
| CodeGenFunction &CGF) { |
| const llvm::Type *SrcTy = Src->getType(); |
| const llvm::Type *DstTy = |
| cast<llvm::PointerType>(DstPtr->getType())->getElementType(); |
| |
| uint64_t SrcSize = CGF.CGM.getTargetData().getTypeAllocSize(SrcTy); |
| uint64_t DstSize = CGF.CGM.getTargetData().getTypeAllocSize(DstTy); |
| |
| // If store is legal, just bitcast the src pointer. |
| if (SrcSize <= DstSize) { |
| llvm::Value *Casted = |
| CGF.Builder.CreateBitCast(DstPtr, llvm::PointerType::getUnqual(SrcTy)); |
| // FIXME: Use better alignment / avoid requiring aligned store. |
| CGF.Builder.CreateStore(Src, Casted)->setAlignment(1); |
| } else { |
| // Otherwise do coercion through memory. This is stupid, but |
| // simple. |
| |
| // Generally SrcSize is never greater than DstSize, since this means we are |
| // losing bits. However, this can happen in cases where the structure has |
| // additional padding, for example due to a user specified alignment. |
| // |
| // FIXME: Assert that we aren't truncating non-padding bits when have access |
| // to that information. |
| llvm::Value *Tmp = CGF.CreateTempAlloca(SrcTy); |
| CGF.Builder.CreateStore(Src, Tmp); |
| llvm::Value *Casted = |
| CGF.Builder.CreateBitCast(Tmp, llvm::PointerType::getUnqual(DstTy)); |
| llvm::LoadInst *Load = CGF.Builder.CreateLoad(Casted); |
| // FIXME: Use better alignment / avoid requiring aligned load. |
| Load->setAlignment(1); |
| CGF.Builder.CreateStore(Load, DstPtr); |
| } |
| } |
| |
| /***/ |
| |
| bool CodeGenModule::ReturnTypeUsesSret(const CGFunctionInfo &FI) { |
| return FI.getReturnInfo().isIndirect(); |
| } |
| |
| const llvm::FunctionType * |
| CodeGenTypes::GetFunctionType(const CGFunctionInfo &FI, bool IsVariadic) { |
| std::vector<const llvm::Type*> ArgTys; |
| |
| const llvm::Type *ResultType = 0; |
| |
| QualType RetTy = FI.getReturnType(); |
| const ABIArgInfo &RetAI = FI.getReturnInfo(); |
| switch (RetAI.getKind()) { |
| case ABIArgInfo::Expand: |
| assert(0 && "Invalid ABI kind for return argument"); |
| |
| case ABIArgInfo::Extend: |
| case ABIArgInfo::Direct: |
| ResultType = ConvertType(RetTy); |
| break; |
| |
| case ABIArgInfo::Indirect: { |
| assert(!RetAI.getIndirectAlign() && "Align unused on indirect return."); |
| ResultType = llvm::Type::getVoidTy(getLLVMContext()); |
| const llvm::Type *STy = ConvertType(RetTy); |
| ArgTys.push_back(llvm::PointerType::get(STy, RetTy.getAddressSpace())); |
| break; |
| } |
| |
| case ABIArgInfo::Ignore: |
| ResultType = llvm::Type::getVoidTy(getLLVMContext()); |
| break; |
| |
| case ABIArgInfo::Coerce: |
| ResultType = RetAI.getCoerceToType(); |
| break; |
| } |
| |
| for (CGFunctionInfo::const_arg_iterator it = FI.arg_begin(), |
| ie = FI.arg_end(); it != ie; ++it) { |
| const ABIArgInfo &AI = it->info; |
| |
| switch (AI.getKind()) { |
| case ABIArgInfo::Ignore: |
| break; |
| |
| case ABIArgInfo::Coerce: |
| ArgTys.push_back(AI.getCoerceToType()); |
| break; |
| |
| case ABIArgInfo::Indirect: { |
| // indirect arguments are always on the stack, which is addr space #0. |
| const llvm::Type *LTy = ConvertTypeForMem(it->type); |
| ArgTys.push_back(llvm::PointerType::getUnqual(LTy)); |
| break; |
| } |
| |
| case ABIArgInfo::Extend: |
| case ABIArgInfo::Direct: |
| ArgTys.push_back(ConvertType(it->type)); |
| break; |
| |
| case ABIArgInfo::Expand: |
| GetExpandedTypes(it->type, ArgTys); |
| break; |
| } |
| } |
| |
| return llvm::FunctionType::get(ResultType, ArgTys, IsVariadic); |
| } |
| |
| void CodeGenModule::ConstructAttributeList(const CGFunctionInfo &FI, |
| const Decl *TargetDecl, |
| AttributeListType &PAL) { |
| unsigned FuncAttrs = 0; |
| unsigned RetAttrs = 0; |
| |
| // FIXME: handle sseregparm someday... |
| if (TargetDecl) { |
| if (TargetDecl->hasAttr<NoThrowAttr>()) |
| FuncAttrs |= llvm::Attribute::NoUnwind; |
| if (TargetDecl->hasAttr<NoReturnAttr>()) |
| FuncAttrs |= llvm::Attribute::NoReturn; |
| if (TargetDecl->hasAttr<ConstAttr>()) |
| FuncAttrs |= llvm::Attribute::ReadNone; |
| else if (TargetDecl->hasAttr<PureAttr>()) |
| FuncAttrs |= llvm::Attribute::ReadOnly; |
| if (TargetDecl->hasAttr<MallocAttr>()) |
| RetAttrs |= llvm::Attribute::NoAlias; |
| } |
| |
| if (CompileOpts.DisableRedZone) |
| FuncAttrs |= llvm::Attribute::NoRedZone; |
| if (CompileOpts.NoImplicitFloat) |
| FuncAttrs |= llvm::Attribute::NoImplicitFloat; |
| |
| if (Features.getStackProtectorMode() == LangOptions::SSPOn) |
| FuncAttrs |= llvm::Attribute::StackProtect; |
| else if (Features.getStackProtectorMode() == LangOptions::SSPReq) |
| FuncAttrs |= llvm::Attribute::StackProtectReq; |
| |
| QualType RetTy = FI.getReturnType(); |
| unsigned Index = 1; |
| const ABIArgInfo &RetAI = FI.getReturnInfo(); |
| switch (RetAI.getKind()) { |
| case ABIArgInfo::Extend: |
| if (RetTy->isSignedIntegerType()) { |
| RetAttrs |= llvm::Attribute::SExt; |
| } else if (RetTy->isUnsignedIntegerType()) { |
| RetAttrs |= llvm::Attribute::ZExt; |
| } |
| // FALLTHROUGH |
| case ABIArgInfo::Direct: |
| break; |
| |
| case ABIArgInfo::Indirect: |
| PAL.push_back(llvm::AttributeWithIndex::get(Index, |
| llvm::Attribute::StructRet | |
| llvm::Attribute::NoAlias)); |
| ++Index; |
| // sret disables readnone and readonly |
| FuncAttrs &= ~(llvm::Attribute::ReadOnly | |
| llvm::Attribute::ReadNone); |
| break; |
| |
| case ABIArgInfo::Ignore: |
| case ABIArgInfo::Coerce: |
| break; |
| |
| case ABIArgInfo::Expand: |
| assert(0 && "Invalid ABI kind for return argument"); |
| } |
| |
| if (RetAttrs) |
| PAL.push_back(llvm::AttributeWithIndex::get(0, RetAttrs)); |
| |
| // FIXME: we need to honour command line settings also... |
| // FIXME: RegParm should be reduced in case of nested functions and/or global |
| // register variable. |
| signed RegParm = 0; |
| if (TargetDecl) |
| if (const RegparmAttr *RegParmAttr |
| = TargetDecl->getAttr<RegparmAttr>()) |
| RegParm = RegParmAttr->getNumParams(); |
| |
| unsigned PointerWidth = getContext().Target.getPointerWidth(0); |
| for (CGFunctionInfo::const_arg_iterator it = FI.arg_begin(), |
| ie = FI.arg_end(); it != ie; ++it) { |
| QualType ParamType = it->type; |
| const ABIArgInfo &AI = it->info; |
| unsigned Attributes = 0; |
| |
| switch (AI.getKind()) { |
| case ABIArgInfo::Coerce: |
| break; |
| |
| case ABIArgInfo::Indirect: |
| Attributes |= llvm::Attribute::ByVal; |
| Attributes |= |
| llvm::Attribute::constructAlignmentFromInt(AI.getIndirectAlign()); |
| // byval disables readnone and readonly. |
| FuncAttrs &= ~(llvm::Attribute::ReadOnly | |
| llvm::Attribute::ReadNone); |
| break; |
| |
| case ABIArgInfo::Extend: |
| if (ParamType->isSignedIntegerType()) { |
| Attributes |= llvm::Attribute::SExt; |
| } else if (ParamType->isUnsignedIntegerType()) { |
| Attributes |= llvm::Attribute::ZExt; |
| } |
| // FALLS THROUGH |
| case ABIArgInfo::Direct: |
| if (RegParm > 0 && |
| (ParamType->isIntegerType() || ParamType->isPointerType())) { |
| RegParm -= |
| (Context.getTypeSize(ParamType) + PointerWidth - 1) / PointerWidth; |
| if (RegParm >= 0) |
| Attributes |= llvm::Attribute::InReg; |
| } |
| // FIXME: handle sseregparm someday... |
| break; |
| |
| case ABIArgInfo::Ignore: |
| // Skip increment, no matching LLVM parameter. |
| continue; |
| |
| case ABIArgInfo::Expand: { |
| std::vector<const llvm::Type*> Tys; |
| // FIXME: This is rather inefficient. Do we ever actually need to do |
| // anything here? The result should be just reconstructed on the other |
| // side, so extension should be a non-issue. |
| getTypes().GetExpandedTypes(ParamType, Tys); |
| Index += Tys.size(); |
| continue; |
| } |
| } |
| |
| if (Attributes) |
| PAL.push_back(llvm::AttributeWithIndex::get(Index, Attributes)); |
| ++Index; |
| } |
| if (FuncAttrs) |
| PAL.push_back(llvm::AttributeWithIndex::get(~0, FuncAttrs)); |
| } |
| |
| void CodeGenFunction::EmitFunctionProlog(const CGFunctionInfo &FI, |
| llvm::Function *Fn, |
| const FunctionArgList &Args) { |
| // If this is an implicit-return-zero function, go ahead and |
| // initialize the return value. TODO: it might be nice to have |
| // a more general mechanism for this that didn't require synthesized |
| // return statements. |
| if (const FunctionDecl* FD = dyn_cast_or_null<FunctionDecl>(CurFuncDecl)) { |
| if (FD->hasImplicitReturnZero()) { |
| QualType RetTy = FD->getResultType().getUnqualifiedType(); |
| const llvm::Type* LLVMTy = CGM.getTypes().ConvertType(RetTy); |
| llvm::Constant* Zero = llvm::Constant::getNullValue(LLVMTy); |
| Builder.CreateStore(Zero, ReturnValue); |
| } |
| } |
| |
| // FIXME: We no longer need the types from FunctionArgList; lift up and |
| // simplify. |
| |
| // Emit allocs for param decls. Give the LLVM Argument nodes names. |
| llvm::Function::arg_iterator AI = Fn->arg_begin(); |
| |
| // Name the struct return argument. |
| if (CGM.ReturnTypeUsesSret(FI)) { |
| AI->setName("agg.result"); |
| ++AI; |
| } |
| |
| assert(FI.arg_size() == Args.size() && |
| "Mismatch between function signature & arguments."); |
| CGFunctionInfo::const_arg_iterator info_it = FI.arg_begin(); |
| for (FunctionArgList::const_iterator i = Args.begin(), e = Args.end(); |
| i != e; ++i, ++info_it) { |
| const VarDecl *Arg = i->first; |
| QualType Ty = info_it->type; |
| const ABIArgInfo &ArgI = info_it->info; |
| |
| switch (ArgI.getKind()) { |
| case ABIArgInfo::Indirect: { |
| llvm::Value* V = AI; |
| if (hasAggregateLLVMType(Ty)) { |
| // Do nothing, aggregates and complex variables are accessed by |
| // reference. |
| } else { |
| // Load scalar value from indirect argument. |
| V = EmitLoadOfScalar(V, false, Ty); |
| if (!getContext().typesAreCompatible(Ty, Arg->getType())) { |
| // This must be a promotion, for something like |
| // "void a(x) short x; {..." |
| V = EmitScalarConversion(V, Ty, Arg->getType()); |
| } |
| } |
| EmitParmDecl(*Arg, V); |
| break; |
| } |
| |
| case ABIArgInfo::Extend: |
| case ABIArgInfo::Direct: { |
| assert(AI != Fn->arg_end() && "Argument mismatch!"); |
| llvm::Value* V = AI; |
| if (hasAggregateLLVMType(Ty)) { |
| // Create a temporary alloca to hold the argument; the rest of |
| // codegen expects to access aggregates & complex values by |
| // reference. |
| V = CreateTempAlloca(ConvertTypeForMem(Ty)); |
| Builder.CreateStore(AI, V); |
| } else { |
| if (!getContext().typesAreCompatible(Ty, Arg->getType())) { |
| // This must be a promotion, for something like |
| // "void a(x) short x; {..." |
| V = EmitScalarConversion(V, Ty, Arg->getType()); |
| } |
| } |
| EmitParmDecl(*Arg, V); |
| break; |
| } |
| |
| case ABIArgInfo::Expand: { |
| // If this structure was expanded into multiple arguments then |
| // we need to create a temporary and reconstruct it from the |
| // arguments. |
| std::string Name = Arg->getNameAsString(); |
| llvm::Value *Temp = CreateTempAlloca(ConvertTypeForMem(Ty), |
| (Name + ".addr").c_str()); |
| // FIXME: What are the right qualifiers here? |
| llvm::Function::arg_iterator End = |
| ExpandTypeFromArgs(Ty, LValue::MakeAddr(Temp,0), AI); |
| EmitParmDecl(*Arg, Temp); |
| |
| // Name the arguments used in expansion and increment AI. |
| unsigned Index = 0; |
| for (; AI != End; ++AI, ++Index) |
| AI->setName(Name + "." + llvm::Twine(Index)); |
| continue; |
| } |
| |
| case ABIArgInfo::Ignore: |
| // Initialize the local variable appropriately. |
| if (hasAggregateLLVMType(Ty)) { |
| EmitParmDecl(*Arg, CreateTempAlloca(ConvertTypeForMem(Ty))); |
| } else { |
| EmitParmDecl(*Arg, llvm::UndefValue::get(ConvertType(Arg->getType()))); |
| } |
| |
| // Skip increment, no matching LLVM parameter. |
| continue; |
| |
| case ABIArgInfo::Coerce: { |
| assert(AI != Fn->arg_end() && "Argument mismatch!"); |
| // FIXME: This is very wasteful; EmitParmDecl is just going to drop the |
| // result in a new alloca anyway, so we could just store into that |
| // directly if we broke the abstraction down more. |
| llvm::Value *V = CreateTempAlloca(ConvertTypeForMem(Ty), "coerce"); |
| CreateCoercedStore(AI, V, *this); |
| // Match to what EmitParmDecl is expecting for this type. |
| if (!CodeGenFunction::hasAggregateLLVMType(Ty)) { |
| V = EmitLoadOfScalar(V, false, Ty); |
| if (!getContext().typesAreCompatible(Ty, Arg->getType())) { |
| // This must be a promotion, for something like |
| // "void a(x) short x; {..." |
| V = EmitScalarConversion(V, Ty, Arg->getType()); |
| } |
| } |
| EmitParmDecl(*Arg, V); |
| break; |
| } |
| } |
| |
| ++AI; |
| } |
| assert(AI == Fn->arg_end() && "Argument mismatch!"); |
| } |
| |
| void CodeGenFunction::EmitFunctionEpilog(const CGFunctionInfo &FI, |
| llvm::Value *ReturnValue) { |
| llvm::Value *RV = 0; |
| |
| // Functions with no result always return void. |
| if (ReturnValue) { |
| QualType RetTy = FI.getReturnType(); |
| const ABIArgInfo &RetAI = FI.getReturnInfo(); |
| |
| switch (RetAI.getKind()) { |
| case ABIArgInfo::Indirect: |
| if (RetTy->isAnyComplexType()) { |
| ComplexPairTy RT = LoadComplexFromAddr(ReturnValue, false); |
| StoreComplexToAddr(RT, CurFn->arg_begin(), false); |
| } else if (CodeGenFunction::hasAggregateLLVMType(RetTy)) { |
| EmitAggregateCopy(CurFn->arg_begin(), ReturnValue, RetTy); |
| } else { |
| EmitStoreOfScalar(Builder.CreateLoad(ReturnValue), CurFn->arg_begin(), |
| false, RetTy); |
| } |
| break; |
| |
| case ABIArgInfo::Extend: |
| case ABIArgInfo::Direct: |
| // The internal return value temp always will have |
| // pointer-to-return-type type. |
| RV = Builder.CreateLoad(ReturnValue); |
| break; |
| |
| case ABIArgInfo::Ignore: |
| break; |
| |
| case ABIArgInfo::Coerce: |
| RV = CreateCoercedLoad(ReturnValue, RetAI.getCoerceToType(), *this); |
| break; |
| |
| case ABIArgInfo::Expand: |
| assert(0 && "Invalid ABI kind for return argument"); |
| } |
| } |
| |
| if (RV) { |
| Builder.CreateRet(RV); |
| } else { |
| Builder.CreateRetVoid(); |
| } |
| } |
| |
| RValue CodeGenFunction::EmitCallArg(const Expr *E, QualType ArgType) { |
| if (ArgType->isReferenceType()) |
| return EmitReferenceBindingToExpr(E, ArgType); |
| |
| return EmitAnyExprToTemp(E); |
| } |
| |
| RValue CodeGenFunction::EmitCall(const CGFunctionInfo &CallInfo, |
| llvm::Value *Callee, |
| const CallArgList &CallArgs, |
| const Decl *TargetDecl) { |
| // FIXME: We no longer need the types from CallArgs; lift up and simplify. |
| llvm::SmallVector<llvm::Value*, 16> Args; |
| |
| // Handle struct-return functions by passing a pointer to the |
| // location that we would like to return into. |
| QualType RetTy = CallInfo.getReturnType(); |
| const ABIArgInfo &RetAI = CallInfo.getReturnInfo(); |
| |
| |
| // If the call returns a temporary with struct return, create a temporary |
| // alloca to hold the result. |
| if (CGM.ReturnTypeUsesSret(CallInfo)) |
| Args.push_back(CreateTempAlloca(ConvertTypeForMem(RetTy))); |
| |
| assert(CallInfo.arg_size() == CallArgs.size() && |
| "Mismatch between function signature & arguments."); |
| CGFunctionInfo::const_arg_iterator info_it = CallInfo.arg_begin(); |
| for (CallArgList::const_iterator I = CallArgs.begin(), E = CallArgs.end(); |
| I != E; ++I, ++info_it) { |
| const ABIArgInfo &ArgInfo = info_it->info; |
| RValue RV = I->first; |
| |
| switch (ArgInfo.getKind()) { |
| case ABIArgInfo::Indirect: |
| if (RV.isScalar() || RV.isComplex()) { |
| // Make a temporary alloca to pass the argument. |
| Args.push_back(CreateTempAlloca(ConvertTypeForMem(I->second))); |
| if (RV.isScalar()) |
| EmitStoreOfScalar(RV.getScalarVal(), Args.back(), false, I->second); |
| else |
| StoreComplexToAddr(RV.getComplexVal(), Args.back(), false); |
| } else { |
| Args.push_back(RV.getAggregateAddr()); |
| } |
| break; |
| |
| case ABIArgInfo::Extend: |
| case ABIArgInfo::Direct: |
| if (RV.isScalar()) { |
| Args.push_back(RV.getScalarVal()); |
| } else if (RV.isComplex()) { |
| llvm::Value *Tmp = llvm::UndefValue::get(ConvertType(I->second)); |
| Tmp = Builder.CreateInsertValue(Tmp, RV.getComplexVal().first, 0); |
| Tmp = Builder.CreateInsertValue(Tmp, RV.getComplexVal().second, 1); |
| Args.push_back(Tmp); |
| } else { |
| Args.push_back(Builder.CreateLoad(RV.getAggregateAddr())); |
| } |
| break; |
| |
| case ABIArgInfo::Ignore: |
| break; |
| |
| case ABIArgInfo::Coerce: { |
| // FIXME: Avoid the conversion through memory if possible. |
| llvm::Value *SrcPtr; |
| if (RV.isScalar()) { |
| SrcPtr = CreateTempAlloca(ConvertTypeForMem(I->second), "coerce"); |
| EmitStoreOfScalar(RV.getScalarVal(), SrcPtr, false, I->second); |
| } else if (RV.isComplex()) { |
| SrcPtr = CreateTempAlloca(ConvertTypeForMem(I->second), "coerce"); |
| StoreComplexToAddr(RV.getComplexVal(), SrcPtr, false); |
| } else |
| SrcPtr = RV.getAggregateAddr(); |
| Args.push_back(CreateCoercedLoad(SrcPtr, ArgInfo.getCoerceToType(), |
| *this)); |
| break; |
| } |
| |
| case ABIArgInfo::Expand: |
| ExpandTypeToArgs(I->second, RV, Args); |
| break; |
| } |
| } |
| |
| // If the callee is a bitcast of a function to a varargs pointer to function |
| // type, check to see if we can remove the bitcast. This handles some cases |
| // with unprototyped functions. |
| if (llvm::ConstantExpr *CE = dyn_cast<llvm::ConstantExpr>(Callee)) |
| if (llvm::Function *CalleeF = dyn_cast<llvm::Function>(CE->getOperand(0))) { |
| const llvm::PointerType *CurPT=cast<llvm::PointerType>(Callee->getType()); |
| const llvm::FunctionType *CurFT = |
| cast<llvm::FunctionType>(CurPT->getElementType()); |
| const llvm::FunctionType *ActualFT = CalleeF->getFunctionType(); |
| |
| if (CE->getOpcode() == llvm::Instruction::BitCast && |
| ActualFT->getReturnType() == CurFT->getReturnType() && |
| ActualFT->getNumParams() == CurFT->getNumParams() && |
| ActualFT->getNumParams() == Args.size()) { |
| bool ArgsMatch = true; |
| for (unsigned i = 0, e = ActualFT->getNumParams(); i != e; ++i) |
| if (ActualFT->getParamType(i) != CurFT->getParamType(i)) { |
| ArgsMatch = false; |
| break; |
| } |
| |
| // Strip the cast if we can get away with it. This is a nice cleanup, |
| // but also allows us to inline the function at -O0 if it is marked |
| // always_inline. |
| if (ArgsMatch) |
| Callee = CalleeF; |
| } |
| } |
| |
| |
| llvm::BasicBlock *InvokeDest = getInvokeDest(); |
| CodeGen::AttributeListType AttributeList; |
| CGM.ConstructAttributeList(CallInfo, TargetDecl, AttributeList); |
| llvm::AttrListPtr Attrs = llvm::AttrListPtr::get(AttributeList.begin(), |
| AttributeList.end()); |
| |
| llvm::CallSite CS; |
| if (!InvokeDest || (Attrs.getFnAttributes() & llvm::Attribute::NoUnwind)) { |
| CS = Builder.CreateCall(Callee, Args.data(), Args.data()+Args.size()); |
| } else { |
| llvm::BasicBlock *Cont = createBasicBlock("invoke.cont"); |
| CS = Builder.CreateInvoke(Callee, Cont, InvokeDest, |
| Args.data(), Args.data()+Args.size()); |
| EmitBlock(Cont); |
| } |
| |
| CS.setAttributes(Attrs); |
| if (const llvm::Function *F = |
| dyn_cast<llvm::Function>(Callee->stripPointerCasts())) |
| CS.setCallingConv(F->getCallingConv()); |
| |
| // If the call doesn't return, finish the basic block and clear the |
| // insertion point; this allows the rest of IRgen to discard |
| // unreachable code. |
| if (CS.doesNotReturn()) { |
| Builder.CreateUnreachable(); |
| Builder.ClearInsertionPoint(); |
| |
| // FIXME: For now, emit a dummy basic block because expr emitters in |
| // generally are not ready to handle emitting expressions at unreachable |
| // points. |
| EnsureInsertPoint(); |
| |
| // Return a reasonable RValue. |
| return GetUndefRValue(RetTy); |
| } |
| |
| llvm::Instruction *CI = CS.getInstruction(); |
| if (Builder.isNamePreserving() && |
| CI->getType() != llvm::Type::getVoidTy(VMContext)) |
| CI->setName("call"); |
| |
| switch (RetAI.getKind()) { |
| case ABIArgInfo::Indirect: |
| if (RetTy->isAnyComplexType()) |
| return RValue::getComplex(LoadComplexFromAddr(Args[0], false)); |
| if (CodeGenFunction::hasAggregateLLVMType(RetTy)) |
| return RValue::getAggregate(Args[0]); |
| return RValue::get(EmitLoadOfScalar(Args[0], false, RetTy)); |
| |
| case ABIArgInfo::Extend: |
| case ABIArgInfo::Direct: |
| if (RetTy->isAnyComplexType()) { |
| llvm::Value *Real = Builder.CreateExtractValue(CI, 0); |
| llvm::Value *Imag = Builder.CreateExtractValue(CI, 1); |
| return RValue::getComplex(std::make_pair(Real, Imag)); |
| } |
| if (CodeGenFunction::hasAggregateLLVMType(RetTy)) { |
| llvm::Value *V = CreateTempAlloca(ConvertTypeForMem(RetTy), "agg.tmp"); |
| Builder.CreateStore(CI, V); |
| return RValue::getAggregate(V); |
| } |
| return RValue::get(CI); |
| |
| case ABIArgInfo::Ignore: |
| // If we are ignoring an argument that had a result, make sure to |
| // construct the appropriate return value for our caller. |
| return GetUndefRValue(RetTy); |
| |
| case ABIArgInfo::Coerce: { |
| // FIXME: Avoid the conversion through memory if possible. |
| llvm::Value *V = CreateTempAlloca(ConvertTypeForMem(RetTy), "coerce"); |
| CreateCoercedStore(CI, V, *this); |
| if (RetTy->isAnyComplexType()) |
| return RValue::getComplex(LoadComplexFromAddr(V, false)); |
| if (CodeGenFunction::hasAggregateLLVMType(RetTy)) |
| return RValue::getAggregate(V); |
| return RValue::get(EmitLoadOfScalar(V, false, RetTy)); |
| } |
| |
| case ABIArgInfo::Expand: |
| assert(0 && "Invalid ABI kind for return argument"); |
| } |
| |
| assert(0 && "Unhandled ABIArgInfo::Kind"); |
| return RValue::get(0); |
| } |
| |
| /* VarArg handling */ |
| |
| llvm::Value *CodeGenFunction::EmitVAArg(llvm::Value *VAListAddr, QualType Ty) { |
| return CGM.getTypes().getABIInfo().EmitVAArg(VAListAddr, Ty, *this); |
| } |
